The present invention relates to the treatment of flooring to improve stain resistance and in particular to flooring with enhanced slip resistance and especially PVC flooring with enhanced slip resistance treated to improve stain resistance and to a method of imparting improved stain resistance to flooring, particularly PVC flooring with enhanced slip resistance.
To provide enhanced slip resistance flooring is generally manufactured having a roughened surface which can be created by embossing the surface or by the addition of particulate material to the main component of the flooring during manufacture.
The roughened surface of the flooring increases the risk of dirt being trapped on the surface. The dirt, depending on its nature, can be compatible with components of the flooring resulting in absorption of the dirt into the surface giving rise to a stain.
It is known to apply a coating to a cured floor with enhanced slip resistance to impart increased stain resistance. However, the application of such a coating generally reduces any surface roughness and thus decreases the slip resistance of the floor.
A particulate material can be sprinkled on top of the coating applied to the cured flooring to impart slip resistance. However the coating applied generally thin and adhesion of the particulate material is thus reduced. Such floorings generally lose their non-slip properties quickly as the particulate material becomes dislodged from the coating.
The present invention provides a flooring material comprising a base portion, a coating portion, imparting improved stain resistance to the flooring material, being positioned in contact with an upper surface of the base portion and creating an upper surface of the flooring material and a first particulate material embedded in the coating portion and at least partially penetrating the base portion to provide a roughening effect of the upper surface of the flooring material for enhanced slip resistance and resistance to wear.
We are therefore able to provide a flooring with enhanced slip resistance having improved stain resistance without affecting the effectiveness as the life of non-slip properties which are achieved by the particulate material.
Preferably the flooring material is a plastics flooring material, for example, PVC, modified olefin/olefin copolymer, plasticised acrylic, polyester.
Preferably, the base portion comprises a plastics material such as a PVC plastisol material. The base portion may include a further particulate material dispersed therein. The further particulate material may be aluminium oxide or any other suitable grit. The base portion may contain a pigment. The base portion may include one or more reinforcing supports, the supports are preferably glass fibre reinforced non-woven supports.
The base portion may be made up of one or more layers of plastics material, preferably up to three layers are envisaged.
The coating portion of the flooring material of the present invention provides improved stain resistance to the flooring material.
It is believed that the coating creates a barrier between the upper surface of the flooring material and the base portion thus preventing exposure of the base portion to possible stainants. The coating may further prevent migration of components of the base portion to the upper surface of the flooring material where contact with possible stainants could occur.
The first particulate material being embedded in the coating portion and penetrating the base portion means that the coating portion does not destroy the non-slip properties of the flooring material and the first particulate material is less likely to become dislodged thus prolonging the life of the non-slip properties of the flooring material.
The first particulate material is known as grit can be any one or more of a number of types of hard particles including silicon carbide, silicas (quartz or coloured/natural sands or flints), aluminium oxide and emery.
The use of a further particulate material throughout the base portion further prolongs the non-slip properties of the flooring material during wear.
The base portion of the flooring material may further contain pigmented PVC chips, quartz chips or other decorative additives to add a decorative effect to the flooring material.
The coating portion preferably merges into the base portion to some extent where the portions meet providing an amount of the coating portion in the base portion, this amount of coating portion preferably decreases as the distance from the meeting of the base portion and the coating portion increases.
The merging of the coating portion into the base portion provides some improved stain resistance in the base portion even after the coating portion has been worn away.
The coating portion may comprise any conveniently available thermoplastic material or, alternatively, thermoset material.
The present invention further provides a method of making a flooring material comprising a base portion, a coating portion imparting improved stain resistance to the flooring material and positioned on an upper surface of the base portion and forming an upper surface of the flooring material and a first particulate material embedded in the coating portion and at least partially penetrating the base portion to provide a roughening effect to the upper surface of the flooring material for enhanced slip resistance and protection from wear, the method comprising the steps of:
a) mixing together the components of the base portion;
b) spreading the mixed components of the base portion on a surface;
c) carrying out at least one application of components of the coating portion in powder form to the components of the base portion;
d) carrying out at least one application of a first particulate material to the components of the base portion before or after applying the components of the coating portion in powder form;
e) heating the powder coated base portion to cause the powder coating to form a film.
Preferably the components of the base portion form a paste when mixed.
The paste is preferably spread on the surface at a controlled thickness, preferably a blade is used to spread the paste at a controlled thickness.
When the powder coated paste is heated the powder coating preferably melts and flows to form the film.
If the powder coating is a thermoplastic material the application of heat in step e) simply melts the coating and allows it to flow and form a film.
If the powder coating is a thermosetting material the application of heat in step e) cures the thermosetting material.
The application of heat in step e) may also serve to gel and cure the base portion where the base portion comprises a PVC plastisol material.
Preferably the components of the coating portion are applied to the paste while it is wet. Alternatively the components of the coating portion may be applied to the base portion after it has been cured.
Applying the components of the coating portion as a powder to a wet paste is advantageous as the components of the coating portion can blend into the wet paste to some extent so that some of the components of the coating portion are present in the wet paste, and therefore the base portion of the flooring material, in decreasing amounts as the distance from the surface of the paste, is increased. The effect is a stratified coating which imparts improved stain resistance even when the coating portion has become worn.
However the components of the coating portion can be applied to the base portion after it has been cured. In this case the components of the coating will not blend with the base portion to give a stratified effect but the advantages of the coating present on the surface of the base portion will still be achieved.
Some of the coating portion in powder form can be mixed with the components of the base portion.
The application of the first particulate material to the powder coated wet paste allows the particulate material to be pressed by embossing through the coating into the paste. This is difficult if the base portion has been cured before coating, but it is possible if the base portion has not set completely.
The application of the first particulate material after the components of the coating portion in powder form will reduce the rate of sinkage of the particulate material into the wet paste thus allowing reproducible deposition of first particulate material by mass per unit area.
The components of the base portion preferably comprise a plastics material such as a PVC plastisol. A further particulate material such as aluminium oxide may be included as a component of the base portion. The PVC plastisol may contain a pigment. The base portion may comprise one or more layers of a plastics material.
A dressing of, for example, silicon carbide may be added to the paste spread at a controlled thickness to confer further slip and wear resistance and give some aesthetic properties. A variety of particles or chips such as PVC chip particles or coloured quartz particles may be added to the paste spread at controlled thickness by, for example, sprinkling the particles from above.
The powder coated paste is heated, most preferably in an oven, to melt the powder coating.
The product is preferably cured for 1-10 minutes, most preferably 3 minutes, at 150-220xc2x0 C., most preferably 190xc2x0 C.
Preferably the product is embossed. Embossing preferably takes place while the product is still hot and soft after curing and involves the application of pressure preferably by means of a roller.
The components of the coating portion in powder form may be applied by a sprinkle system, a roller pick-up/brush off type system or a spray system.
More than one application of the components of the coating portion in powder form may be necessary.
More than one application of the first particulate material is possible.
The presence of the coating portion is likely to reduce water absorption of the flooring material of the present invention. The presence of the coating portion also reduces the amount of volatile organic compounds given off.